Check the following lines in your ~/.muttrc if you're migrating from
mutt 1.2.x.

set charset=big5
set locale="zh_TW.Big5"
set send_charset="big5:gb2312:us-ascii:iso-8859-1:utf-8:x-unknown"
charset-hook us-ascii big5
charset-hook iso-8859-1 big5

Please execute the following command if you encounter problem with
legacy bbs:

echo "set bbsislame=yes" >> ~/.muttrc
